Send a part number, a photo, or a whole BOM — we supply it and stand behind it. Worldwide shipping to 80+ countries.

3G Electric
RFQ CartGet a QuoteSign inSign up
SIEMENS IEC 5SY42255 A-Curve 2-Pole UL1077 Supplementary Protector - A-Curve, 2-Pole UL1077 DIN Rail-Mount Supplementary Protectors
SIEMENS IECA-Curve, 2-Pole UL1077 DIN Rail-Mount Supplementary Protectors

SIEMENS IEC 5SY42255 A-Curve 2-Pole UL1077 Supplementary Protector

The SIEMENS IEC Supplementary Protector (SKU 5SY42255, MPN 5SY42255) is a 25 A, A-Curve, 2-Pole UL1077 DIN Rail-Mount supplementary protector from the 5SY4 series. It features a screw-clamp connection and is rated at…

SKU 3G-OTH-127909

Brand
SIEMENS IEC
Item
5SY42255 A-Curve 2-Pole UL1077 Supplementary Protector
Category
A-Curve, 2-Pole UL1077 DIN Rail-Mount Supplementary Protectors
Available to Order
Trade pricing by quote — replies within 24h
Qty
WhatsApp an engineerMessage via Telegram
No account needed — your quote request goes straight to our engineers. A free account lets you track quotes and re-order faster.
Worldwide Shipping
Air & sea freight
Datasheet on Request
Technical specs
1-Day Quote
Replies within 24h

Local availability & support — Singapore

Local office
20 Woodlands Link #09-05, Singapore 738733
Phone
+65 8878 8355
Delivery
Same-day or next-business-day delivery within Singapore for in-stock items; 7–14 days for factory-order parts from Europe.
Payment
Invoicing in SGD. PayNow, bank transfer, and corporate PO accepted.
Ships to
Singapore

Technical Specifications

SIEMENS IEC
Manufacturer Part Number
5SY42255
Type
10kA at 400V AC, Screw Clamp, 5SY4
AC
400V
DC
72V

Technical Documents

No technical documents available for this product.
Request documentation →
Not sure this is the right part? Get a recommendation.

Need installation or engineering help?

Installation, commissioning, maintenance plans, system design, and bundled product + service quotes — one team handles the full scope.
Talk to an engineer

Ask a question

SIEMENS IEC Products
3G Electric (S) Pte. Ltd. — Singapore

Product Description

The SIEMENS IEC Supplementary Protector (SKU 5SY42255, MPN 5SY42255) is a 25 A, A-Curve, 2-Pole UL1077 DIN Rail-Mount supplementary protector from the 5SY4 series. It features a screw-clamp connection and is rated at 400V AC with a breaking capacity of 10kA at 400V AC, and 72V DC.

Frequently Asked Questions

What is the SIEMENS IEC Supplementary Protector 5SY42255 used for?

The SIEMENS IEC Supplementary Protector 5SY42255 is used to protect branch circuits and equipment from overcurrent and short circuits in industrial control panels, HVAC systems, and automation applications. It is a UL1077 listed, DIN rail-mount device suitable for 400V AC and 72V DC systems.

What are the specifications of the SIEMENS 5SY42255 supplementary protector?

The SIEMENS 5SY42255 is a 25 A, A-Curve, 2-pole supplementary protector from the 5SY4 series. It has a screw-clamp connection, rated voltage of 400V AC and 72V DC, and a breaking capacity of 10kA at 400V AC. It is UL1077 listed for DIN rail mounting.

Where to buy the SIEMENS 5SY42255 supplementary protector worldwide?

You can source the SIEMENS 5SY42255 supplementary protector worldwide through 3G Electric, a global industrial equipment distributor. We handle full logistics, customs clearance, and delivery to your location. Contact us for availability and lead time.

How to install the SIEMENS 5SY42255 supplementary protector?

To install the SIEMENS 5SY42255, mount it on a standard DIN rail, ensure the circuit is de-energized, and connect wires using the screw-clamp terminals. Follow the manufacturer's torque specifications and verify polarity for DC applications. Always consult local electrical codes.

Used in

Common applications for SIEMENS IEC
Motor control centers — Siemens 5SY4 D-curve supplementary protectors (e.g., 5SY42108) for motor branch circuit protection
HVAC equipment — A-curve protectors (e.g., 5SY42255) for compressor and fan motor overcurrent protection
Industrial conveyor systems — 4-pole D-curve protectors (e.g., 5SY44168) for three-phase motor protection with neutral
Pump control panels — 2-pole supplementary protectors (e.g., 5SY42038) for single-phase pump motor protection
Machine tool control circuits — A-curve protectors (e.g., 5SY44155) for solenoid valve and relay protection
Power distribution sub-panels — 4-pole protectors (e.g., 5SY44155) for three-phase branch circuit protection in light industrial settings

SIEMENS IEC Products

3G Electric supplies SIEMENS IEC a-curve, 2-pole ul1077 din rail-mount supplementary protectors. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.

You might also need

Burners & Combustion →Pumps & Compressors →Spare Parts →All Products →

Compatible alternatives & equivalents

Cross-referenced by specification & description
This 2-pole supplementary protector from the 5SY4 series features an A-Curve trip characteristic and a rated current of 10 A. It is rated for 400 V AC with a breaking capacity of 10 kA at 400 V AC and 72 V DC. The unit uses screw clamp terminals and is designed for DIN-rail mounting, suitable for overcurrent and short-circuit protection in branch circuits of industrial control panels, HVAC systems, and automation equipment
SIEMENS IEC
This 2-pole supplementary protector from the 5SY4 series features an A-Curve trip characteristic and a rated current of 10 A. It is rated for 400 V AC with a breaking capacity of 10 kA at 400 V AC and 72 V DC. The unit uses screw clamp terminals and is designed for DIN-rail mounting, suitable for overcurrent and short-circuit protection in branch circuits of industrial control panels, HVAC systems, and automation equipment
A 3 A, A-Curve, 2-pole supplementary protector from the 5SY4 series, rated 400V AC and 72V DC with a breaking capacity of 10kA at 400V AC. Features screw clamp terminals and mounts on DIN rail. Suitable for overcurrent and short-circuit protection in branch circuits and equipment within industrial control panels, HVAC systems, and automation applications
SIEMENS IEC
A 3 A, A-Curve, 2-pole supplementary protector from the 5SY4 series, rated 400V AC and 72V DC with a breaking capacity of 10kA at 400V AC. Features screw clamp terminals and mounts on DIN rail. Suitable for overcurrent and short-circuit protection in branch circuits and equipment within industrial control panels, HVAC systems, and automation applications
This 2-pole supplementary protector from the 5SY4 series features an A-Curve trip characteristic and is UL1077 listed. Rated 63 A, 400V AC and 72V DC, with a breaking capacity of 10kA at 400V AC. Terminals are screw clamp type. Designed for DIN rail mounting in branch circuit and equipment protection applications
SIEMENS IEC
This 2-pole supplementary protector from the 5SY4 series features an A-Curve trip characteristic and is UL1077 listed. Rated 63 A, 400V AC and 72V DC, with a breaking capacity of 10kA at 400V AC. Terminals are screw clamp type. Designed for DIN rail mounting in branch circuit and equipment protection applications
This 16 A, A-Curve, 2-pole supplementary protector from the 5SY4 series is rated for 400V AC with a breaking capacity of 10kA at 400V AC and 72V DC. It features screw clamp terminals and mounts on a standard DIN rail. Suitable for overcurrent and short-circuit protection in branch circuits and equipment within industrial control panels, HVAC systems, and automation applications
SIEMENS IEC
This 16 A, A-Curve, 2-pole supplementary protector from the 5SY4 series is rated for 400V AC with a breaking capacity of 10kA at 400V AC and 72V DC. It features screw clamp terminals and mounts on a standard DIN rail. Suitable for overcurrent and short-circuit protection in branch circuits and equipment within industrial control panels, HVAC systems, and automation applications

More from SIEMENS IEC

View all SIEMENS IEC parts →
SIEMENS IEC supplementary protector, 1 A rated current, A-Curve trip characteristic, 2-pole configuration. UL1077 listed for DIN rail mounting. Rated 400V AC and 72V DC with 10kA breaking capacity at 400V AC. Screw clamp terminals. Suitable for overload and short-circuit protection in control panels, HVAC, and machinery
SIEMENS IEC
SIEMENS IEC supplementary protector, 1 A rated current, A-Curve trip characteristic, 2-pole configuration. UL1077 listed for DIN rail mounting. Rated 400V AC and 72V DC with 10kA breaking capacity at 400V AC. Screw clamp terminals. Suitable for overload and short-circuit protection in control panels, HVAC, and machinery
This 2-pole supplementary protector from the 5SY4 series is rated 50 A with A-curve tripping characteristics. It is UL1077 recognized for branch circuit and control equipment protection in industrial control panels, HVAC systems, and machinery. Rated 400V AC and 72V DC with a breaking capacity of 10kA at 400V AC, it features screw clamp terminals for DIN rail mounting
SIEMENS IEC
This 2-pole supplementary protector from the 5SY4 series is rated 50 A with A-curve tripping characteristics. It is UL1077 recognized for branch circuit and control equipment protection in industrial control panels, HVAC systems, and machinery. Rated 400V AC and 72V DC with a breaking capacity of 10kA at 400V AC, it features screw clamp terminals for DIN rail mounting
40 A, A-Curve, 2-pole supplementary protector for overcurrent and short-circuit protection in branch circuits and equipment. Rated 400V AC (10kA breaking capacity) and 72V DC. Features screw clamp terminals and DIN rail mount. UL1077 listed
SIEMENS IEC
40 A, A-Curve, 2-pole supplementary protector for overcurrent and short-circuit protection in branch circuits and equipment. Rated 400V AC (10kA breaking capacity) and 72V DC. Features screw clamp terminals and DIN rail mount. UL1077 listed
This 32 A, A-Curve, 2-pole supplementary protector from the 5SY4 series is UL1077 listed for overcurrent and short-circuit protection. It features screw-clamp terminals and mounts on DIN rail. Rated 400V AC with 10kA breaking capacity and 72V DC. Suitable for branch circuit and equipment protection in control panels and machinery
SIEMENS IEC
This 32 A, A-Curve, 2-pole supplementary protector from the 5SY4 series is UL1077 listed for overcurrent and short-circuit protection. It features screw-clamp terminals and mounts on DIN rail. Rated 400V AC with 10kA breaking capacity and 72V DC. Suitable for branch circuit and equipment protection in control panels and machinery
This 13 A, A-Curve, 2-pole supplementary protector is UL1077 listed for DIN rail mounting. It provides overcurrent and short-circuit protection for branch circuits and control equipment in industrial control panels, HVAC systems, and machinery. Rated 400V AC and 72V DC with a breaking capacity of 10kA at 400V AC, it features screw clamp terminals
SIEMENS IEC
This 13 A, A-Curve, 2-pole supplementary protector is UL1077 listed for DIN rail mounting. It provides overcurrent and short-circuit protection for branch circuits and control equipment in industrial control panels, HVAC systems, and machinery. Rated 400V AC and 72V DC with a breaking capacity of 10kA at 400V AC, it features screw clamp terminals
A 6 A, A-Curve, 2-pole supplementary protector for DIN rail mounting. Rated 400V AC with 10kA breaking capacity and 72V DC. Features screw-clamp terminals. Suitable for overcurrent and short-circuit protection in branch circuits and equipment
SIEMENS IEC
A 6 A, A-Curve, 2-pole supplementary protector for DIN rail mounting. Rated 400V AC with 10kA breaking capacity and 72V DC. Features screw-clamp terminals. Suitable for overcurrent and short-circuit protection in branch circuits and equipment
20 A, A-Curve, 2-pole supplementary protector from the 5SY4 series. Rated 400V AC and 72V DC with a breaking capacity of 10kA at 400V AC. Features screw clamp terminals and is UL1077 listed for DIN rail mounting. Used for overcurrent and short-circuit protection in branch circuits and equipment within industrial control panels, HVAC systems, and automation applications
SIEMENS IEC
20 A, A-Curve, 2-pole supplementary protector from the 5SY4 series. Rated 400V AC and 72V DC with a breaking capacity of 10kA at 400V AC. Features screw clamp terminals and is UL1077 listed for DIN rail mounting. Used for overcurrent and short-circuit protection in branch circuits and equipment within industrial control panels, HVAC systems, and automation applications
This 2-pole supplementary protector from the 5SY4 series is rated 1.6 A with an A-curve trip characteristic. It is UL1077 listed for branch circuit and equipment overcurrent protection in industrial control panels, HVAC systems, and automation applications. Rated 400V AC and 72V DC with a breaking capacity of 10kA at 400V AC, it features screw clamp terminals and mounts on a DIN rail
SIEMENS IEC
This 2-pole supplementary protector from the 5SY4 series is rated 1.6 A with an A-curve trip characteristic. It is UL1077 listed for branch circuit and equipment overcurrent protection in industrial control panels, HVAC systems, and automation applications. Rated 400V AC and 72V DC with a breaking capacity of 10kA at 400V AC, it features screw clamp terminals and mounts on a DIN rail